The field of the invention is refrigerant system servicing and the invention relates more particularly to a method and apparatus for determining contaminants in a refrigerant gas.
Since refrigerant gases can become contaminated with contaminants such as water or acid which contaminants tend to degrade the metal components of the refrigerant system, it is important to detect these contaminants as soon as possible to minimize the damage done to the system. Various methods have been used to do this, such as those shown in U.S. Pat. Nos. 5,071,768 and 4,923,806. Such systems, however, are cumbersome and expensive to use. Apparatus for testing low pressure refrigerant gas is shown in U.S. Pat. No. 4,803,843. Other patents showing gas testing systems are disclosed in U.S. Pat. Nos. 3,544,276; 4,014,216; and 4,071,319.
It is important that a device and method be available which device is portable, easy to use and relatively foolproof. There are numerous new refrigerant gases and some prior art methods that are useful for a particular refrigerant gas in most cases is not useful with a different refrigerant gas.
Recently, the Air Condition and Refrigerant Institute (ARI) has established threshold limit values for the allowable amount of contamination in refrigerant gas. This is in response to laws that prohibit venting or the release of spent refrigerants into the atmosphere. Such refrigerants are being recovered, reclaimed or recycled into external tanks or cylinders. In order to assure that the collected gas is suitable for reuse, the purity of that gas must be determined. For example, the limit value of moisture in refrigerants must not exceed 10.0 ppm, and for acid, not greater than 1.0 ppm. The present state of knowledge does not permit field sampling to such a high order of sensitivity.